Greasers wore Belstaff and rockers wore leather and got wet. Everthing I owned was covered in Black slime from them and the trousers, still got wet and in winter could not bend arms and legs as they were solid when cold.
Only people I knew who wore Belstaff were trails riders and the like, certainly none of the guys I hung around with wore Belstaff. From memory I think Belstaff was more used by people living in the country, unlike us who lived on a council estate. That's my own observation from two guys I worked with, both wore Belstaff, or at least wax jackets, and they kept them in good condition, the last thing I would have called them were Greasers. Maybe the term was used differently in other parts of the country, than in Suffolk.
Whatever you wore, as you said you got wet and cold in the winter.
Greasers or Rockers to me were both the same and wiki seems to agree with me.
By 1965, the term greaser had also been introduced to Great Britain[4][5][6] and, since then, the terms greaser and rocker have become synonymous within the British Isles although used differently in North America and elsewhere. Rockers were also derisively known as Coffee Bar Cowboys.
Ian